After moving tons of earth for an expansion, Stafford Regional Airport in Virginia faced an embarrassing problem: severe and seemingly irreversible baldness. Virtually nothing grew on its dusty, damaged land.

The airport’s worried manager, Ed Wallis, tried different treatments before he was advised to consult with officials at the Blue Plains Advanced Water Treatment Plant, a sprawling facility at the southern tip of the District that processes 375 million gallons of the area’s wastewater per day.

Airport officials liked what they saw and began accepting a dark substance called a biosolid from Blue Plains. Five months later, grass started to sprout. A year later, it was thigh-high.

“It was unbelievable,” Wallis said.

That transformation a decade ago is a legend at Blue Plains, the first thing officials from the plant mentioned recently while promoting theirbiosolid fertilizer. That’s a fancy scientific marketing name that masks what the biosolids truly are — sludge made primarily from human waste.

Probably the world’s original fertilizer, this cleaned and treated version of what was long known as “night soil” may well loom large in the future, too.

Seven million tons of the sludge is produced annually in this country, and transforming it into biosolids is an effective way to get rid of it, according to the Environmental Protection Agency.

Blue Plains, for instance, for years has squeezed water out of sludge, added lime to it and dried it. This partially treated Class B biosolid is then trucked free of charge to farms, most of them in Virginia, where the fertilizer is used with substantial restrictions. The yearly cost to the facility of getting rid of the Class B solids is $10 million.

But the economics of Blue Plains biosoil could change soon, now that the facility plans to spend $400 million to upgrade its product to Class A biosolids. These are deemed safe enough to put in your mouth — though it’s not encouraged — and would carry few restrictions.

And like Milorganite, a Class A biosolid produced by the Milwaukee Metropolitan Sewage District on a smaller scale, the Blue Plains Class A solids could eventually be sold.

The plans, however, have met resistance.

Opponents say no class of biosolid can be viewed as safe. In areas where it’s been spread, residents have complained of foul odors that last for weeks, queasiness and problems with their lungs. One man said a substance spread on a neighboring farm gave him a life-threatening illness.

“Now they’ve got this great product, but it still has the potential to contain chemicals,” said Chris Nidel, a lawyer who represented residents in Surry County, Va., who said foul-smelling Class B biosolids made them sick.

The debate over biosolids is yet another example of how difficult it can be to go green — efforts to be environmentally forward-thinking can be quickly viewed as a negative development to others. Windmills in Spain kill birds by the thousands, bird lovers say. Solar panel installations in the Mojave desert wrongly forced the removal of endangered turtles, wildlife defenders say.

To its opponents, Blue Plains, the world’s largest advanced wastewater treatment plant, is another villain for producing and spreading biosolids.

But the plant is dealing with a problem created by area residents who flush toilets, brush their teeth and wash dishes, sending millions of tons of waste down the drain. Wastewater officials must treat it and somehow get rid of it.

They can’t simply put it in a landfill. because sludge would eventually take up far too much space, said Thomas R. Fox, a professor of forestry at Virginia Tech.

“I think you always have to figure out . . . what to do, how to move forward, what’s the cost, and what’s the benefit, based on the best science available,” he said. “The problem won’t go away.”

In 2014, Blue Plains plans to start a new process to remove pathogens from the biosolids. Initially, it will give away the Class A fertilizer to farmers for free. But it’s potentially valuable because it can be used on food crops.

Improving the process

The EPA encourages the production of biosolids under strict federal standards. Wastewater treatment plants in 14 states are certified to make biosolids, and plants four additional states are seeking certification.

There are, however, known hazards: Class B biosolids contain viruses that can cause diseases such as Ebola, which can sickens and potentially kill people. Farmers need permits to spread the Class B fertilizer on pastures and are forbidden from using it for food crops. Any field treated with Class B biosolids has to be cordoned off for 30 days or more.

But Class A biosolids don’t produce the pathogens, the stink or the costs of producing and potentially discharging Class B biosolids, Fox said. A process known as thermal hydrolysis reduces the volume of sludge by cooking it in one set of tanks, and it is then sent to another set of heated tanks where half of the solid is chewed away by microbes.

As they eat, the bugs excrete methane that would be sent to yet another tank and converted to energy to help fire about a third of the plant, saving $11 million a year in electricity, officials said.

Fox said repeated testing has shown that Class A biosolids are not a threat to people, animals or waterways. Long-term, the goal is to produce a Blue Plains biosolid to be sold at hardware stores.

Chris Peot, the biosolids manager at Blue Plains, said that only trace amounts of metals and chemicals are found in Class A and Class B sludge.

“These chemicals show up in such infinitesimal amounts that they don’t show any risk,” Peot said. “These products we have in our homes — toothpastes, dish soaps and hand sanitizers — have more. We put that stuff in our mouths and spit it down the sink.”

But people who oppose using treated sludge as fertilizers aren’t sympathetic, and are suspicious about the safety of Class A biosolids as well as the lower-grade product.

Ed Merrifield, president of Potomac Riverkeeper, said biosolids contain the same nitrogen and phosphorous that creates fish-killing dead zones in the Chesapeake Bay. “The basic issue is it’s supposed to be kept out of our rivers,” Merrifield said. But “it’s applied improperly and goes right back into our rivers.”

Henry Staudinger is also not convinced that he wants to see any kind of biosolid used as fertilizer. Staudinger, a retired lawyer, said he became ill when sludge was spread on land next to his farm in Shenandoah County, Va.

“I ended up in the emergency room with an allergic reaction, difficulty breathing, vomiting,” he said. “I had a pond near my house, and there was a fish kill . . . But I couldn’t get anybody to investigate it or do anything about it.

“I don’t have most of my sense of smell, but this stuff was overpowering,” Staudinger said.

But at Stafford Regional Airport, Ed Wallis is sold on biosolid. When workers spread it on 380 acres around the runways at Stafford airport, it restored land that had been ruined during an expansion project.

“We started in the spring and it grew in the fall,” Wallis said of the grass. “It was still growing in December.”

Without the free Class B biosolid, Wallis said he would have spent $80,000 just for lime to use in restoring the damaged land. New, rich topsoil, along with trucks to haul it and workers to spread it, would have cost much more.

But the fecal biosolids definitely have their drawbacks, he said, as well as their benefits.

“Residents complained about the odors,” Wallis said. “You can’t blame anybody who’s sitting out in their yard, trying to grill a steak.”

Darryl Fears has worked at The Washington Post for more than a decade, mostly as a reporter on the National staff. He currently covers the environment, focusing on the Chesapeake Bay and issues affecting wildlife.

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